RC框架-钢管混凝土腋撑结构抗震性能分析

腋撑是设置于梁柱节点区域的短斜撑,用于提高结构抗水平力作用性能。与普通框架支撑相比,腋撑能提高建筑的有效使用空间,提高建筑的使用功能。腋撑可采用钢支撑、混凝土支撑以及耗能支撑等形式。钢管混凝土腋撑相比于钢腋撑,其轴向承载力较高;相比于混凝土腋撑和耗能腋撑,其施工更为方便。以新沂市某中学教学楼为背景工程,分别构建RC框架和RC框架-钢管混凝土腋撑结构模型,计算两种结构的振型、自振周期、能力曲线以及刚度退化速率等动力性能指标,通过对比分析,探讨增加钢管混凝土腋撑后对结构抗震性能的影响。研究表明,增设钢管混凝土腋撑后,结构的水平极限承载力和初始刚度大幅提高,层间位移明显减小,RC框架-钢管混凝土腋撑结构是一种抗震性能较好的新型结构。

Seismic Performance Analysis of RC Frame-CFST Haunch Brace Structure

Haunch brace is the short brace in the area of beam-column joints used to improve the structural performance of the anti-level force.Compared with the ordinary frame brace,the haunch brace can improve the functions of the building space and building.The haunch brace can be in the form of steel brace concrete brace and energy dissipation brace.Compared with the steel brace,the CFST haunch brace has higher bearing capacity and compared with the concrete brace and energy dissipation brace,its construction is more convenient.This paper takes a middle school in Xinyi city as a background,models the RC frame and RC frame-CFST haunch brace.To study its impact on the frame＇s seismic behavior,the dynamic performance indicators includes the natural vibration period,capacity curve and the rate of stiffness degradation.The result shows that the CFST haunch brace can improve the frame＇s bearing capacity and initial stiffness and can also reduce the story drift.The RC frame-CFST haunch brace is a new structure that has a good seismic behavior.